The lowest temperature obtained in laboratory conditions is -273.14 degrees Celsius, which is 4.21 degrees Celsius

The lowest temperature obtained in laboratory conditions is -273.14 degrees Celsius, which is 4.21 degrees Celsius below the boiling point of helium. which is the boiling point of helium.

If it is known from the condition of the problem that the boiling point of helium is 4.21 degrees higher than the lowest temperature obtained in the laboratory, then adding 4.21 degrees to the lowest temperature in laboratory conditions, we get the boiling point of helium:
-273.14 + 4.21 = -268.93.
Answer: we got that helium begins to boil at a temperature of -268.93 degrees Celsius.